package com.superhelper.common.utils;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.InputStreamReader;
import java.security.InvalidKeyException;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;

import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.superhelper.common.Consts;
import com.superhelper.common.exception.ServiceException;

public class RSAUtils {
    private static final Logger log = LoggerFactory.getLogger(RSAUtils.class);
    private static RSAPublicKey publicKey;
    private static RSAPrivateKey privateKey;
    /**
     * 字节数据转字符串专用集合
     */
    private static final char[] HEX_CHAR = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e',
            'f' };

    /**
     * 随机生成密钥对
     */
    public static void genKeyPair(String filePath) {
        // KeyPairGenerator类用于生成公钥和私钥对，基于RSA算法生成对象
        KeyPairGenerator keyPairGen = null;
        try {
            keyPairGen = KeyPairGenerator.getInstance("RSA");
        } catch (NoSuchAlgorithmException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        // 初始化密钥对生成器，密钥大小为96-1024位
        keyPairGen.initialize(1024, new SecureRandom());
        // 生成一个密钥对，保存在keyPair中
        KeyPair keyPair = keyPairGen.generateKeyPair();
        // 得到私钥
        RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
        // 得到公钥
        RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
        try {
            // 得到公钥字符串
            String publicKeyString = Base64.encode(publicKey.getEncoded());
            // 得到私钥字符串
            String privateKeyString = Base64.encode(privateKey.getEncoded());
            // 将密钥对写入到文件
            FileWriter pubfw = new FileWriter(filePath + "/publicKey.key");
            FileWriter prifw = new FileWriter(filePath + "/privateKey.key");
            BufferedWriter pubbw = new BufferedWriter(pubfw);
            BufferedWriter pribw = new BufferedWriter(prifw);
            pubbw.write(publicKeyString);
            pribw.write(privateKeyString);
            pubbw.flush();
            pubbw.close();
            pubfw.close();
            pribw.flush();
            pribw.close();
            prifw.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 从文件中输入流中加载公钥
     * 
     * @param in
     *            公钥输入流
     * @throws Exception
     *             加载公钥时产生的异常
     */
    public static String loadPublicKeyByFile(boolean online) {
        try {
            BufferedReader br = new BufferedReader(new InputStreamReader(RSAUtils.class.getClassLoader()
                    .getResourceAsStream("pub-" + (online ? "product" : "test") + ".key"), "utf-8"));
            String readLine = null;
            StringBuilder sb = new StringBuilder();
            while ((readLine = br.readLine()) != null) {
                sb.append(readLine);
            }
            br.close();
            return sb.toString();
        } catch (Exception e) {
            log.error("load public key error", e);
            throw new ServiceException(Consts.Code.SECURE_ERROR, null);
        }
    }

    /**
     * 从字符串中加载公钥
     * 
     * @param publicKeyStr
     *            公钥数据字符串
     * @throws Exception
     *             加载公钥时产生的异常
     */
    public static RSAPublicKey loadPublicKeyByStr(String publicKeyStr) {
        try {
            byte[] buffer = Base64.decode(publicKeyStr);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            X509EncodedKeySpec keySpec = new X509EncodedKeySpec(buffer);
            return (RSAPublicKey) keyFactory.generatePublic(keySpec);
        } catch (Exception e) {
            log.error("load public key error", e);
            throw new ServiceException(Consts.Code.SECURE_ERROR, null);
        }
    }

    /**
     * 从文件中加载私钥
     * 
     * @param keyFileName
     *            私钥文件名
     * @return 是否成功
     * @throws Exception
     */
    public static String loadPrivateKeyByFile(boolean online) {
        try {
            BufferedReader br = new BufferedReader(new InputStreamReader(RSAUtils.class.getClassLoader()
                    .getResourceAsStream("pri-" + (online ? "product" : "test") + ".key"), "utf-8"));
            String readLine = null;
            StringBuilder sb = new StringBuilder();
            while ((readLine = br.readLine()) != null) {
                sb.append(readLine);
            }
            br.close();
            return sb.toString();
        } catch (Exception e) {
            throw new ServiceException(Consts.Code.SECURE_ERROR, null);
        }
    }

    public static RSAPrivateKey loadPrivateKeyByStr(String privateKeyStr) {
        try {
            byte[] buffer = Base64.decode(privateKeyStr);
            PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(buffer);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            return (RSAPrivateKey) keyFactory.generatePrivate(keySpec);
        } catch (Exception e) {
            throw new ServiceException(Consts.Code.SECURE_ERROR, null);
        }
    }

    /**
     * 公钥加密过程
     * 
     * @param publicKey
     *            公钥
     * @param plainTextData
     *            明文数据
     * @return
     * @throws Exception
     *             加密过程中的异常信息
     */
    public static String encrypt(String toBeEncrypt, boolean online) {
        if (publicKey == null) {
            publicKey = RSAUtils.loadPublicKeyByStr(RSAUtils.loadPublicKeyByFile(online));
        }
        Cipher cipher = null;
        try {
            // 使用默认RSA
            cipher = Cipher.getInstance("RSA");
            // cipher= Cipher.getInstance("RSA", new BouncyCastleProvider());
            cipher.init(Cipher.ENCRYPT_MODE, publicKey);
            byte[] output = cipher.doFinal(toBeEncrypt.getBytes("utf-8"));
            return Base64.encode(output);
        } catch (Exception e) {
            log.error("load public key error", e);
        }
        return StringUtils.EMPTY;
    }

    /**
     * 私钥加密过程
     * 
     * @param privateKey
     *            私钥
     * @param plainTextData
     *            明文数据
     * @return
     * @throws Exception
     *             加密过程中的异常信息
     */
    public static byte[] encrypt(RSAPrivateKey privateKey, byte[] plainTextData) throws Exception {
        if (privateKey == null) {
            throw new Exception("加密私钥为空, 请设置");
        }
        Cipher cipher = null;
        try {
            // 使用默认RSA
            cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.ENCRYPT_MODE, privateKey);
            byte[] output = cipher.doFinal(plainTextData);
            return output;
        } catch (NoSuchAlgorithmException e) {
            throw new Exception("无此加密算法");
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
            return null;
        } catch (InvalidKeyException e) {
            throw new Exception("加密私钥非法,请检查");
        } catch (IllegalBlockSizeException e) {
            throw new Exception("明文长度非法");
        } catch (BadPaddingException e) {
            throw new Exception("明文数据已损坏");
        }
    }

    /**
     * 私钥解密过程
     * 
     * @param privateKey
     *            私钥
     * @param cipherData
     *            密文数据
     * @return 明文
     * @throws Exception
     *             解密过程中的异常信息
     */
    public static byte[] decrypt(RSAPrivateKey privateKey, byte[] cipherData) throws Exception {
        if (privateKey == null) {
            throw new Exception("解密私钥为空, 请设置");
        }
        Cipher cipher = null;
        try {
            // 使用默认RSA
            cipher = Cipher.getInstance("RSA");
            // cipher= Cipher.getInstance("RSA", new BouncyCastleProvider());
            cipher.init(Cipher.DECRYPT_MODE, privateKey);
            byte[] output = cipher.doFinal(cipherData);
            return output;
        } catch (NoSuchAlgorithmException e) {
            throw new Exception("无此解密算法");
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
            return null;
        } catch (InvalidKeyException e) {
            throw new Exception("解密私钥非法,请检查");
        } catch (IllegalBlockSizeException e) {
            throw new Exception("密文长度非法");
        } catch (BadPaddingException e) {
            throw new Exception("密文数据已损坏");
        }
    }

    /**
     * 公钥解密过程
     * 
     * @param publicKey
     *            公钥
     * @param cipherData
     *            密文数据
     * @return 明文
     * @throws Exception
     *             解密过程中的异常信息
     */
    public static String decrypt(String cipherData, boolean online) {

        if (privateKey == null) {
            privateKey = RSAUtils.loadPrivateKeyByStr(RSAUtils.loadPrivateKeyByFile(online));
        }
        try {
            Cipher cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.DECRYPT_MODE, privateKey);
            byte[] output = cipher.doFinal(Base64.decode(cipherData));
            return new String(output, "utf-8");
        } catch (Exception e) {
            e.printStackTrace();
            throw new ServiceException(Consts.Code.SECURE_ERROR, e.getMessage());
        }
    }

    /**
     * 字节数据转十六进制字符串
     * 
     * @param data
     *            输入数据
     * @return 十六进制内容
     */
    public static String byteArrayToString(byte[] data) {
        StringBuilder stringBuilder = new StringBuilder();
        for (int i = 0; i < data.length; i++) {
            // 取出字节的高四位 作为索引得到相应的十六进制标识符 注意无符号右移
            stringBuilder.append(HEX_CHAR[(data[i] & 0xf0) >>> 4]);
            // 取出字节的低四位 作为索引得到相应的十六进制标识符
            stringBuilder.append(HEX_CHAR[(data[i] & 0x0f)]);
            if (i < data.length - 1) {
                stringBuilder.append(' ');
            }
        }
        return stringBuilder.toString();
    }

    private static ExecutorService es = Executors.newCachedThreadPool();

    public static void main(String[] args) throws Exception {
        String filepath = "d:";

        // String token1 =
        // "D3g8ywhNuWsT1WmKaOBja84IKcaJOQE/5JGmiTEpAfd6zb5Zz/o5hfNSFrXehGeKY7Mc42e0NfPjFHdx/+MyPzRkQ5WLj+tGk3g2QSpOLkxXh+DUSOnPJZBi1etBzDnPI5BF3jVCDVKzGt99FeS7QHT39MLdl7dhmr0viL7NkHY=";
        // String token =
        // "sq3QwiihZBZ7XG2YHHMsQQSq7snBfQ/EBwoZP2utp6ngPNiOBqqjOQem6Gh2UunDGdgACoZEnEpSp+9aqgYPRNfANaZfAOxsF5KSQ+c0N/nMI3+8aUDW4HXpCkaBGTF9Wi1TxII06Kwz/A594c0U8Yb6DCEybsIfzMMbyPI9UUo=";
        // for (int i = 0; i < 10; i++) {
        // es.execute(new Runnable() {
        //
        // @Override
        // public void run() {
        // String result = decrypt(
        // "DSlcfz3RW/Vg3mThsdcPIyQ6OoD+chMoBHbDHnt0+/7qr3kP0/DEchuAQwVz5Egq9nmhP5eE8rUWhXsdbdqAXz0OMV1WHZFzu3xBh56m/xj6iyynUYb5dwdeC2Cwe1Rm4ee0aDBL5fTEEPvZHT6DcrzqCf2yHAWw5z73FjE1ejw=",
        // true);
        // System.out.println(result);
        // }
        // });
        //
        // }

        genKeyPair(filepath);
        //
        // System.out.println("--------------公钥加密私钥解密过程-------------------");
        // String plainText = "ihep_公钥加密私钥解密";
        // // 公钥加密过程
        // byte[] cipherData = RSAUtils.encrypt(plainText.getBytes());
        // String cipher = Base64.encode(cipherData);
        // // 私钥解密过程
        // byte[] res =
        // RSAUtils.decrypt(RSAUtils.loadPrivateKeyByStr(RSAUtils.loadPrivateKeyByFile(filepath)),
        // Base64.decode(cipher));
        // String restr = new String(res);
        // System.out.println("原文：" + plainText);
        // System.out.println("加密：" + cipher);
        // System.out.println("解密：" + restr);
        // System.out.println();
        //
        // System.out.println("--------------私钥加密公钥解密过程-------------------");
        // plainText = "ihep_私钥加密公钥解密";
        // // 私钥加密过程
        // cipherData =
        // RSAUtils.encrypt(RSAUtils.loadPrivateKeyByStr(RSAUtils.loadPrivateKeyByFile(filepath)),
        // plainText.getBytes());
        // cipher = Base64.encode(cipherData);
        // // 公钥解密过程
        // res =
        // RSAUtils.decrypt(RSAUtils.loadPublicKeyByStr(RSAUtils.loadPublicKeyByFile(filepath)),
        // Base64.decode(cipher));
        // restr = new String(res);
        // System.out.println("原文：" + plainText);
        // System.out.println("加密：" + cipher);
        // System.out.println("解密：" + restr);
        // System.out.println();

    }
}
